Structure and method for separation and transfer of semiconductor thin films onto dissimilar substrate materials

• US 20030122141A1
• Filed: 12/16/2002
• Published: 07/03/2003
• Est. Priority Date: 08/23/2000
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Wong, William S., Kneissl, Michael A.
• Granted Patent: US 6,627,921 B2
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: H01L 21/2007 Bonding of semiconductor wafers to insulating substrates or to semiconducting substrates using an intermediate insulating layer H01L21/2011 takes precedence; bonding of semiconductor wafers to semiconductor wafers for junction formation H01L21/187
• CPC Class Codes: H01L 2221/6835 used as a support during build up manufacturing of active devices
• CPC Class Codes: H01L 2221/68363 used in a transfer process involving transfer directly from an origin substrate to a target substrate without use of an intermediate handle substrate
• CPC Class Codes: H01L 2224/83894 Direct bonding, i.e. joining surfaces by means of intermolecular attracting interactions at their interfaces, e.g. covalent bonds, van der Waals forces
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01327 Intermediate phases, i.e. intermetallics compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01S 5/0213 Sapphire, quartz or diamond based substrates
• CPC Class Codes: H01S 5/0215 Bonding to the substrate
• CPC Class Codes: H01S 5/0217 Removal of the substrate
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP
• CPC Class Codes: Y10S 438/977 Thinning or removal of substrate

Abstract

A method for placing nitride laser diode arrays on a thermally and electrically conducting substrate is described. The method uses an excimer laser to detach the nitride laser diode from the sapphire growth substrate after an intermediate substrate has been attached to the side opposite the sapphire substrate. A secondary layer is subsequently deposited to act as a transfer support structure and bonding interface. The membrane is released from the intermediate substrate and a thermally conducting substrate is subsequently bonded to the side where the sapphire substrate was removed. Similarly, the secondary layer may be used as the new host substrate given an appropriate thickness is deposited prior to removal of the intermediate substrate.

Claims

1. A method for making a nitride laser diode structure comprising:

providing a semiconductor membrane having an optically transparent substrate attached on a first side of said semiconductor membrane;

attaching a support substrate to a second side of said semiconductor membrane;

removing said optically transparent substrate from said first side of said semiconductor membrane;

placing an elastically-compliant support layer on said first side of said semiconductor membrane;

releasing said semiconductor membrane from said support substrate; and

placing said elastically-compliant support layer on a substrate having a high thermal conductivity.

2. The method of claim 1 wherein said optically transparent substrate is comprised of sapphire.

3. The method of claim 1 wherein the step of attaching said thermally conducting substrate to said first side of said semiconductor membrane includes putting a solder layer on said thermally conducting substrate.

4. The method of claim 3 wherein said solder layer includes a material selected from the group consisting of In, PbSn, and AuSn.

5. The method of claim 1 wherein the step of attaching said support substrate to said second side of said semiconductor membrane includes using wax to attach said support substrate to said second side.

6. The method of claim 1 wherein the step of removing said optically transparent substrate includes exposing said optically transparent substrate to laser light.

7. The method of claim 6 wherein the step of removing said optically transparent substrate includes polishing of said optically transparent substrate prior to exposure to laser light.

8. The method of claim 1 wherein said semiconductor membrane is comprised of In, Ga, Al and N.

9. The method of claim 1 wherein said thermally conducting substrate includes a material selected from the group consisting of silicon, silicon carbide, copper, gold and diamond.

10. The method of claim 1 wherein said nitride laser diode structure is an array of nitride laser diodes.

11. A method for making a nitride laser diode structure comprising:

providing a semiconductor membrane having a first crystal plane, said semiconductor membrane having an optically transparent substrate attached to a first side of said semiconductor membrane and having an electrode attached to a second side of said semiconductor membrane;

attaching a support substrate to said second side of said semiconductor membrane;

removing said optically transparent substrate from said first side of said semiconductor membrane;

placing a metal layer on said first side of said semiconductor membrane;

removing said support substrate from said second side of said semiconductor membrane; and

attaching a high thermal conductivity substrate having a second crystal plane to said first side of said semiconductor membrane such that said first and said second crystal planes are aligned.

12. The method of claim 11 wherein said nitride laser diode structure is an array of nitride laser diodes.

13. The method of claim 12 further comprising:

cleaving said thermally conducting substrate along said second crystal plane and cleaving said semiconductor membrane along said first crystal plane to make facets in said array of nitride laser diodes.

14. The method of claim 11 wherein said thermally conducting substrate is selected from the group consisting of silicon, GaAs or copper substrates.

15. A nitride laser diode structure comprising:

a secondary support layer that is elastically compliant;

an n-metal layer attached to said secondary support layer;

a semiconductor membrane having a first and second surface, said first surface being attached to said n-metal layer; and

a p-contact attached to said second surface of said semiconductor membrane.

16. The nitride laser diode structure of claim 15 wherein said secondary support layer is comprised of copper.